Maybe you missed the article (and the accompanying video), but this trike is about waist high. It doesn’t even clear the front height of a sedan, let alone be visible to someone in an SUV or pickup truck going at near highway speeds.

I wouldn’t consider this safe, unless it had a huge flag on it, similar to what you see on recumbent bicycles. Motorcycles with a rider on them are at least significantly taller and more visible compared to this thing.